JERUSALEM - Israeli and American forces on Tuesday fired a salvo of Patriot missiles as part of a joint exercise to test air defenses, and Israel's defense minister said a U.S.-Iraq war is "apparently inevitable."

A witness saw six missiles fired from a battery deep in southern Israel's Negev Desert. The Israeli military confirmed six launches and said more missiles could be fired in the next few days.

During the 1991 Gulf War (news - web sites), Iraq fired 39 Scud missiles at Israel, causing damage but few casualties. All had conventional warheads. Officials are concerned that Iraq might aim chemical or biological weapons at Israel in a new conflict.

Speaking during a visit to navy shipyards in Haifa, Defense Minister Shaul Mofaz said that the U.S. administration is "determined to carry out the American attack, and I can say with the appropriate caution that this attack appears to be inevitable."

Mofaz was inspecting the refitting of an Israeli Dolphin-class submarine, which experts say could be armed with nuclear missiles, giving Israel a second-strike capability if it were attacked with weapons of mass destruction.

Israel received three of the German-made submarines. The first, which arrived in July 1999, has been undergoing refitting for a year and a half, Mofaz said, but he did not give details of what changes were made. He said the work would "restore the full operational capabilities of the Dolphin."

Purchase of the Dolphin-class submarines was canceled once because of the price tag but restored after the 1991 Gulf War.

The current U.S.-Israel maneuvers, codenamed "Juniper Cobra," deployed Patriots around the country, practiced moving military convoys from place to place and used a U.S. radar boat at sea on the eastern Mediterranean, diplomats and Israeli security officials said.

Launched on Jan. 19, the exercise is now drawing to a close, a U.S. official said.

The Maariv newspaper said Tuesday that Patriot batteries now in place, and three more on their way from Germany, fire an upgraded version of the missile, which failed to hit any Scuds in the 1991 war. They are being used as a second line of defense, while the main role goes to the U.S.-Israeli Arrow missiles, designed to take out incoming Scuds at high altitude.

Israel's Homefront Command on Tuesday began distributing leaflets that explain how to seal a room in the home against chemical or biological attack and how to use gas masks and protection kits issued to every citizen. The brochures also give pointers on buying commercially made air filtering systems for homes and bomb shelters.